4 multiplied by 2 by 1 because its her hours for the weeks no other way to calculate this problem
Answer:
50.24m²
Step-by-step explanation:
area of circle
= 3.14 × r²
= 3.14 × 4 × 4
= 50.24
Answer:
x < -1.5 U x > 9.6
Step-by-step explanation:
12x + 7 < -11
x < -1.5
5x - 8 > 40
5x > 48
x > 9.6
Answer:
14.99 hours
Step-by-step explanation:
The formula for half-life is given as,
R/R' = 2ᵃ/ᵇ...................... Equation 1
Where R= Original mass of sodium-24, R' = mass of Sodium-24 after disintegration, a = Total time taken for sodium-24 to disintegrate, b = half-life of sodiun-24.
Given: R = 1 kg, R' = 0.0156 kg, a = 90 hours
Substitute into equation 1 and solve for b
1/(0.0156) = 2⁹⁰/ᵇ
Taking the log of both side
log[1/(0.0156)] = log(2⁹⁰/ᵇ)
log[1/(0.0156)] = 90/b(log2)
90/b = log[1/(0.0156)]/log2
90/b = 6.0023
b = 90/6.0023
b = 14.99 hours
b = 14.99 hours.
Hence the half-life of Sodium-24 is 14.99 hours
